For many years, inventors have attempted to adapt tire valve stems with an air pressure gauge. However, some of these inventions either did not work or failed to have the flexibility necessary for the abuse taken by valve stems. It is common for drivers to utilize an accessory tire gauge, which requires the removal of the valve stem cover, thereby soiling the driver's fingers in doing so.
Accordingly, it is desirable for drivers to be aware of their vehicle tires' air pressure at a glance, as it is desirable to have this function available in a manner that boasts safety.
Furthermore, owners of these devices desire that the device be permanently installed from within the tire rim to the outside rather than from the outside so as to prevent the theft of these devices. Additionally, in a worst-case event, if a combination valve becomes severely damaged, the combination valve would be required to maintain tire pressure at any cost.
The applicant is aware of several attempts in prior art to provide means of combining a valve stem and a tire gauge. For example, reference may be had to U.S. Pat. No. 1,423,447 of Noe, issued Jul. 18, 1922, which describes a rigid valve stem with a pressure gauge primarily designed to adapt to bicycles. However, this device fails to provide the required flexibility to resist breakage from the day to day abuse imposed onto the device.
Another example of prior art may be had in referring to U.S. Pat. No. 3,230,968 of Struby, issued Jan. 25, 1966, which depicts a permanently installed valve having a color code indicator. However, this valve is very short, making it difficult to view a reading. Additionally, its rigidity may pose a problem in abusive conditions. Furthermore, the telescopic portion is subjected to the elements of dirt and granular material which would therefore render the gauge inaccurate.
Another example of prior art may be had in referring to U.S. Pat. No. 3,906,988 of Mottram, issued Sep. 23, 1975, which illustrates a rigid valve and gauge combination. Again, this valve is rigid and fails to have the ability to flex if stricken.
While many prior art inventions have succeeded in providing vehicle operators with a combination air pressure gauge and valve stem, none have succeeded in offering flexibility with accuracy, safety and durability in such valve stems.